*DESIGN VARIABLES

Keyword type: model definition

This option is used to define the design variables for a sensitivity study. The parameter TYPE is required and can take the value COORDINATE or ORIENTATION. In case of COORDINATE a second line is needed to define the nodes whose coordinates are to be changed. These nodes should be part of the surface of the structure (a change in position of nodes internal to the structure does not change the geometry). They will be varied in a direction locally orthogonal to the structure (in-surface motions do not change the geometry). In the case of ORIENTATION the sensitivity of all orientations expressed by *ORIENTATION cards is calculated successively.

This keywork card should only occur once in the input deck. If it occurs more than once only the first occurrence is taken into account.

First line:

• *DESIGN VARIABLES
• Enter the TYPE parameter and its value.

Following line if TYPE=COORDINATE:

• Node set containing the design variables.

Example:

*DESIGN VARIABLES,TYPE=COORDINATE
N1

defines the set N1 as the node set containing the design variables.

Example files: sensitivity_I.